This application is related to the field of vehicle control systems and, more particularly, to a remote start system and related methods for vehicles.
Vehicle security systems are widely used to deter vehicle theft, prevent theft of valuables from a vehicle, deter vandalism, and to protect vehicle owners and occupants. A typical automobile security system, for example, includes a central processor or controller connected to a plurality of vehicle sensors. The sensors, for example, may detect opening of the trunk, hood, doors, windows, and also movement of the vehicle or within the vehicle. Ultrasonic and microwave motion detectors, vibration sensors, sound discriminators, differential pressure sensors, and switches may be used as sensors. In addition, radar sensors may be used to monitor the area proximate the vehicle.
The controller typically operates to give an alarm indication in the event of triggering of a vehicle sensor. The alarm indication may typically be a flashing of the lights and/or the sounding of the vehicle horn or a siren. In addition, the vehicle fuel supply and/or ignition power may be selectively disabled based upon an alarm condition.
A typical security system also includes a receiver associated with the controller that cooperates with one or more remote transmitters typically carried by the user as disclosed, for example, in U.S. Pat. No. 4,383,242 to Sassover et al. and U.S. Pat. No. 5,146,215 to Drori. The remote transmitter may be used to arm and disarm the vehicle security system or provide other remote control features from a predetermined range away from the vehicle. Also related to remote control of a vehicle function U.S. Pat. No. 5,252,966 to Lambropoulous et al. discloses a remote keyless entry system for a vehicle. The keyless entry system permits the user to remotely open the vehicle doors or open the vehicle trunk using a small handheld transmitter.
Unfortunately, the majority of vehicle security systems need to be directly connected by wires to individual vehicle devices, such as the vehicle horn or door switches of the vehicle. In other words, a conventional vehicle security system is hardwired to various vehicle components, typically by splicing into vehicle wiring harnesses or via interposing T-harnesses and connectors. The number of electrical devices in a vehicle has increased so that the size and complexity of wiring harnesses has also increased. For example, the steering wheel may include horn switches, an airbag, turn-signal and headlight switches, wiper controls, cruise control switches, ignition wiring, an emergency flasher switch, and/or radio controls. Likewise, a door of a vehicle, for example, may include window controls, locks, outside mirror switches, and/or door-panel light switches.
In response to the increased wiring complexity and costs, vehicle manufacturers have begun attempts to reduce the amount of wiring within vehicles to reduce weight, reduce wire routing problems, decrease costs, and reduce complications which may arise when troubleshooting the electrical system. For example, some manufacturers have adopted multiplexing schemes to reduce cables to three or four wires and to simplify the exchange of data among the various onboard electronic systems as disclosed, for example, in xe2x80x9cThe Thick and Thin of Car Cablingxe2x80x9d by Thompson appearing in the IEEE Spectrum, February 1996, pp. 42-45.
Implementing multiplexing concepts in vehicles in a cost-effective and reliable manner may not be easy. Successful implementation, for example, may require the development of low or error-free communications in what can be harsh vehicle environments. With multiplexing technology, the various electronic modules or devices may be linked by a single signal wire in a bus also containing a power wire, and one or more ground wires. Digital messages are communicated to all modules over the data communications bus. Each message may have one or more addresses associated with it so that the devices can recognize which messages to ignore and which messages to respond to or read.
The Thompson article describes a number of multiplexed networks for vehicles. In particular, the Grand Cherokee made by Chrysler is described as having five multiplex nodes or controllers: the engine controller, the temperature controller, the airbag controller, the theft alarm, and the overhead console. Other nodes for different vehicles may include a transmission controller, a trip computer, an instrument cluster controller, an antilock braking controller, an active suspension controller, and a body controller for devices in the passenger compartment.
A number of patent references are also directed to digital or multiplex communications networks or circuits, such as may be used in a vehicle. For example, U.S. Pat. No. 4,538,262 Sinniger et al. discloses a multiplex bus system including a master control unit and a plurality of receiver-transmitter units connected thereto. Similarly, U.S. Pat. No. 4,055,772 to Leung discloses a power bus in a vehicle controlled by a low current digitally coded communications system. Other references disclosing various vehicle multiplex control systems include, for example, U.S. Pat. No. 4,760,275 to Sato et al.; U.S. Pat. No. 4,697,092 to Roggendorf et al.; and U.S. Pat. No. 4,792,783 to Burgess et al.
Several standards have been proposed for vehicle multiplex networks including, for example, the Society of Automotive Engineers xe2x80x9cSurface Vehicle Standard, Class B Data Communications Network Interfacexe2x80x9d, SAE J1850, July 1995. Another report by the SAE is the xe2x80x9cSurface Vehicle Information Report, Chrysler Sensor and Control (CSC) Bus Multiplexing Network for Class xe2x80x98Axe2x80x99 Applicationsxe2x80x9d, SAE J2058, July 1990. Many other networks are also being implemented or proposed for communications between vehicle devices and nodes or controllers.
In addition, to vehicle security and remote keyless entry functions, another type of desirable vehicle remote control function is remotely starting the vehicle engine when the owner is away from the vehicle. Such remote starting can be used in cold climates to warm the engine and/or run the passenger compartment heater, to thereby prevent freezing or for the user""s comfort. Conversely, remote engine starting can enable the air conditioning to run to cool the vehicle""s interior before the vehicle user enters the vehicle.
Unfortunately, conventional vehicle control systems, such as aftermarket remote engine starting systems, are for hardwired connection to vehicle devices and are not readily adaptable to a vehicle including a data communications bus. Moreover, remote starting of the engine presents additional difficulties compared to some other vehicle control applications. This is so because starting the engine may require certain vehicle conditions are correct prior to starting the engine and while the engine is running with the vehicle unattended. It may also be necessary for a remote starter system to bypass an immobilizer device which is part of the security system of some vehicles. For example, U.S. Pat. No. 5,612,578 to Drew entitled xe2x80x9cVehicle Engine Start Control Apparatus Including Interface Device Facilitating Installation and Related Methodsxe2x80x9d discloses a remote start system which is hardwire connected via mating plugs for more conveniently bypassing an immobilizer circuit based upon a coded resistance of the ignition key.
A remote starter system may also desirably be able to interface with one or more vehicle controllers, such as for engine management and transmission control, for example. In addition, a remote starter system, even if it were adapted for a communications bus and devices for one particular model, model year, and manufacturer, may not be compatible with any other models, model years, or manufacturers.
In view of the foregoing background it is therefore an object of the invention to provide a remote start control system and related method for a vehicle comprising a data communications bus and at least one vehicle device connected to the data communications bus.
It is another object of the invention to provide such a remote starter system and associated method wherein the system is adapted to operate with different vehicles.
These and other objects, features and advantages in accordance with the present invention are provided by a vehicle remote start control system including at least one vehicle device associated with starting an engine of the vehicle, a remote start transmitter, a receiver at the vehicle for receiving signals from the remote start transmitter, and a vehicle remote start controller. The vehicle remote start controller is connected to the data communications bus for communicating with the at least one vehicle device. The remote start controller is also connected to the receiver, and is responsive to signals from the remote start transmitter to cause starting of the vehicle.
The at least one vehicle device associated with starting the engine of the vehicle may comprise at least one controller, such as the engine management controller or the transmission controller, for example. Alternately, or additionally, the at least one vehicle device associated with starting the engine of the vehicle may comprise at least one vehicle sensor. For example, the vehicle sensor may be one or more of a brake sensor, a transmission sensor, a hood sensor, or an engine speed sensor.
In some embodiments, the vehicle may also include an engine starter circuit, and a security immobilizer circuit connected to the engine starter circuit. The security immobilizer circuit is for selectively enabling the engine starter, such as in response to a coded key or transponder. In such embodiments, the remote start controller may bypass the security immobilizer circuit to enable remote starting.
The remote start transmitter may be a remote handheld transmitter to be carried by a user when away from the vehicle, for example. The remote start signal may also be supplied via a communications network, such as including at least a central station transmitter.
Another aspect of the invention relates to providing compatibility with different vehicle types. The remote start controller may comprise a multi-vehicle compatible remote start controller. The multi-vehicle compatible remote start controller may generate at least one set of command signals on the data communications bus for the at least one vehicle device. The at least one set of command signals may comprise at least one working command signal and at least one non-working command signal for a given vehicle to thereby provide command compatibility with a plurality of different vehicles.
In addition, for reading communications from the vehicle devices, the multi-vehicle compatible remote start controller may store a set of device codes for a given vehicle device for a plurality of different vehicles, read a device code from the data communications bus, and determine a match between a read device code and the stored device codes to thereby provide compatibility with a plurality of different vehicles.
In another embodiment, the multi-vehicle compatibility may be provided by equipping the remote start controller with a desired signal enabling function. This function or feature is for enabling operation using a desired set of signals for a corresponding desired vehicle from a plurality of sets of signals for different vehicles to thereby provide compatibility with a plurality of different vehicles.
A method aspect of the invention is for remotely starting a vehicle engine in a vehicle comprising a data communications bus and at least one vehicle device associated with starting the vehicle engine. The method preferably comprises receiving signals at the vehicle from a remote start transmitter, connecting a vehicle remote start controller to the data communications bus for communicating with the at least one vehicle device, and using the vehicle remote start controller to start the vehicle engine based upon signals received from the remote start transmitter and based upon communication over the data communications bus with the at least one vehicle device.
FIG. 1 is a schematic block diagram of a first embodiment of a vehicle remote start control system connected to a data communications bus and other hardwired devices in accordance with the invention.
FIG. 2 is a schematic diagram illustrating processing of command signals generated on the data communications bus in the remote start control system of FIG. 1.
FIG. 3 is a schematic diagram illustrating processing of a code read from the data communications bus in accordance with a first embodiment of the remote start control system of FIG. 1.
FIG. 4 is a schematic diagram illustrating processing of a code read from the data communications bus in accordance with a second embodiment of the remote start control system of FIG. 1.
FIG. 5 is a simplified schematic block diagram of a second embodiment of a vehicle remote start control system connected to a data communications bus in accordance with the invention.
FIG. 6 is a schematic block diagram of a first embodiment of a desired signal enabling portion of the vehicle remote start control system of FIG. 5.
FIG. 7 is a schematic block diagram of a second embodiment of a desired signal enabling portion of the vehicle remote start control system of FIG. 5.
FIG. 8 is a schematic block diagram of a third embodiment of a desired signal enabling portion of the vehicle remote start control system of FIG. 5.
FIG. 9 is a schematic block diagram of a fourth embodiment of a desired signal enabling portion of the vehicle remote start control system of FIG. 5.
FIG. 10 is a schematic block diagram of fifth embodiment of a desired signal enabling portion of the vehicle remote start control system of FIG. 5.